euler 34

#include <bits/stdc++.h>
using namespace std;

constexpr int f[] = {1, 1, 2, 6, 24, 120, 720, 5040, 40320, 362880};
bool ok(int n) {
    int b = n;
    while (n) {
        b -= f[n % 10];
        n /= 10;
    }
    return !b;
}

signed main() {
    ios::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);
    int64_t s = 0;
    // do 40585 pa ke zakoci, najbolje samo soberi gi dvata broja lol
    for (int i = 3; i < 40586; i++) {
        if (ok(i)) {
            s += i;
            cerr << i << '\n';
        }
    }
    cout << s;
}